The present invention relates to filtration of fluid systems and more specifically to filtration in lubrication systems for gas turbine engines.
In pressurized fluid systems, such as a lubrication system or a fuel system in a gas turbine engine, fluid is directed through a network of passages to specified regions of a machine to serve numerous functions, such as lubrication and cooling. In a gas turbine engine, the lubrication system directs a substantial volume of a lubricating fluid to engine bearing compartments to provide the necessary lubrication and cooling of the bearings contained therein. This lubricating fluid may carry a residual quantity of particulate matter, such as metallic filings, sediments, or other solids generated by material wear occurring at sliding or impacting surfaces within the bearing compartments and other internal components of the gas turbine engine.
It is well known that filtering particulate matter from the lubricating fluid can minimize the wear to bearings and other internal components in the gas turbine engine. Particulate matter is filtered from the lubricating fluid by a screen or other filter positioned along the passages of the lubrication system. Over time, these filters and screens can become partially or fully blocked by the particulate matter, thereby starving the downstream bearings and components of the pressure and flow of lubricating fluid that is required for proper function. In some prior art systems, the screens have been designed to burst at a predetermined pressure, so as to preserve a threshold pressure and flow of lubricating fluid to the bearings and other components to preserve proper function of the bearings and components. However, the particulate matter previously collected by the screens is introduced into the lubricating fluid when the screen bursts and can cause wear and reduced life to the bearings and components downstream.